Grinding kill



Jan. 1. 19,24

D. CGLE ET Ai.

4 Sheets-Sheet l Jan. 1

D. COLE ET A- GRNDING MLL Filed April FS. 1922 4 Sheets-Sheet 2 Jan. 1,1924 1,479,172 D. COLE E? As.

GRND ING M PLL 4 Shasta-Sheet Fied April.

D. COLE ET AL GMNDINQ NULL Filed April w22 4 Sheets-Sheet 4` if; f Inf,

rammed Jan. 1, i924.

UNITED STATES PATENT OFFICE.

DAVID COLE AND JULIUS G. BERGMAN, F EL PASO, TEXAS.

GRINDING MILL.

Application tiled April 6,

To ai] whom it 'may concern.'

Be it known that we, DAvin COLE, a citizen oi the l'nitcd States. and.lULtUs G. BERG- M.\.\'. a subject of the King' of Sweden, re.- sidingat. El Paso. in the county ot' lill Paso and State ot' Texas, haveinvented certain nen` and useful Improvements in (irinding,r Mills, ofwhich the following is a specification.

This invention relates to grinding mills and particularly to' grindingmills of the rod type. Certain features ot the invention are applicableto mills of other types, and are capable of general use wherever arotary drum or cylinder must be supported on a peripheral bearing.

Rod Igrinding mills consist ot' an elongated cylindrical drum. rotatableon a horizontal -zutis` and containing a large number ot' ull `ring' andsupporting rollers.

loose parallel rods ot' steel lyingr horizontally in thc drum andextending substantially the lentire length of the drum. 'ltcn the drumis rotated the tumbling: ot' the rods performs the grinding function,and such mills are comiitncr into extensive usc for grinding ores. 'i

Rod grinding-mills are peculiarly desirable because ot' their superiorgrinding action but their construction and operation have heretoforepresented serious dilliculties which arose 'from the great weight ot'the loaded grinding drum, and the practical necessity ot' having atleast: ont removable head. The purpose ot' the removable head is topermit the mill to be run slmi'ly with the rods exposed so that thtIrods cau be in spectetl, and. worn rods can be removed. loro rods arelikely to become lient and .snarled with troublesome results. and quickand easy inspection is essential to practical and economical operation.

A removable head may he had by eliminatinc' one of the end trunuionscommon in grinditngr mills, and substituting a riding' Since.supporting' rollers have only line. contacts with the riding ring alarge number of rollers must he used to avoid excessive crushingstresses on the lines of cont act` between rollers and riding rings. Theuse of more than two rollers makes necessary some load crumbling means.livrer cqualizers can be. usedk but their consti-oet ion is expensiveand is prohihitivclj; expensive except with a very small number ofro'lers. 1t is hard to secure 1922. Serial No. 550,016.

accurate alinement of the rollers, and harder still to maintain it underthe conditions of actual service. llren slight misalinement of asupporting;r roller. leads to destructive wear and serious waste ot'power, under the heavy loads encountered in this Service.

Another ditliculty incident to the use of rod grinding mills is the factthat the wear on both rods and lining is greater at the feed end than atthe discharge end, so that it has been thc practise heretofore toreverse the rods and lining` in the drum at intervals to equalize thewear. This is a laborious and expensive operation.

The present invention overcomes these difficulties by providitfinr aself-equalizing type of bearing in which the stresses are all favorableto the maintenance of alinement. Stated broadly. the inventioncontemplates the use ot' a riding,r ring or rings running on a series ofrollers, such series of rollers being supported on or between linkchains adjustably mounted at their ends and prop erly stabilized toprevent rocking or pitching ot' the supported drum. All the rollers,roller supporting bearings, hinge pins, and chain links may be madeinterchangeable, and may be so standardized as to be capable of use inmills of this type differing considerably in size. Thesecharacteristicspermit accurate and yet inexpensive. manufacture. 'lhe simplicity of thechain structure permits the use. without und-ue complication or expense,otl a relatively large number of rolle and this so reduces the load perroller thatlit ispossihle to avail of commercial sizes of hall or rollerbearings. This makes the use of antitriction hearings economicallypossible and leads to the saving of about one third ol' the powerotherwise necessary. v

lVhile one equaliz/.iug roller bearing of the type herein disclosed andclaimed may be used with that type ot mill having one riding' ring andone trunnion bearing, the full advantages of the invention are securedby using t wo equalizing bearings and two riding rings and dispensingwith trtmnions altogether. It then becomes possible to make the drumsymmetrical with respect to its transverse median plane and to design'the feed and discharge ittings so that they may be transposed. A drum soconstructed may be li'l'ted from its bearings, turned end for end, andmounted in reversed position on the bearings. This can be accomplishedin a few minutes with the crane equipment usuali): availaiale, and,after the interchange of thc feed and discharge iittings has the Sallieetieet as the reversal of the lining and rods. as well as the additionalbeneficial effect of reversely meshing the driving pinion and ring gear.Since the continuous operation of man v plants is largely dependent onthe continuous operation of the ,grinding mills the practical importanceof the above feature is manifest.

Preferred embodiments of the invention are shown in the accompanyingdrawings, in Whicl1:

Fig. 1 is a side view partly in elevation and partlxy in axial sectionof the complete mill.

Fig. 2 is a section on the iine ot' F i 4. 1.

fig. I is an elevation of a chain carrier yoke with chain and rollsattached, showing the arrangement of the chain stabilizers. Parts ofthis figure are broken away to show how the chain carrier yoke isadjusted.

Fig. 4 is a plan view ot' the parts shown in Fig. 3.

Fig. 5 is a` section on an enlarged scale takt-u on the line 5 5 of Fig.3.

Fig. is a fragmentary View, similar to a portion of Fig. 2.y hut showinga modified construction.

Fig. i is a tragitti-nier)y plan of the supY portiimr roll structureshown in Fig.

Fig. S is :in end elevation oi' the support iner roll structure shown inFig. (i.

The cylilnlrical grinding drum is made up of four substantiallyidentical flanged sections 11 hoited together and two identicalremovable heads 12. The ring dri\'ing-gear 13 is mounted with its web 14clamped between the ilauires ot' the two middle sections 11. and twoidentical riding' rings 15 are each similarly mounted with their webs 16clamped hrlneen the flanges of a corre-- Spondiner cud section 1l andthc adjacent one of the two middle sections 11. The feed scoop 17 andthe discharge fitting 18 are interehangzeahle with cach other andareremovably mounted hy means of bolts or the equivalent. T his produces aVstructure which is symmetrical with lreference to the median plane otgear 13, except vfor the feed scoop 17 and fitting 18, and hence may heturned end for end on its supportingr hearings. rPhe feed scoop li' andfitting 18 may he interchanged with each other as conditions require.

Any suitable form of lining 19 may he used and this may he removablymounted in any suitable manner, for example hy studs with nuts 20 (seeFig. 2i. The drive mechanism may be of any desired type, and is shown asconsisting of Jinion 22 on the motor shaft, gear 23 meshing therewith.and

pinion 24. fast on a` shaft with gear 23 and meshing with ringl gear 13.

The ridi g rings 15 run on corresponding sets of rollers each setsupporte-d b f two equaliziug Chains. Two slightly dit erent embodimentsot' this inventive concept are shown in the drawings and thatillustrated in Figs. 1 to 5 inclusive will first be de, scribed.

The main base frame is shown at 25 and upon this are mounted twoidentical cast frames 26. The frames 26 each carry a correspondingbearing structure and as these bearing structures are alike adescription of one will sntiiee.

Mounted at opposite ends of each frame 26 are the tivo chain carrieryokes 27. Each of these has a hase plate 28 and two inclined .opstandingarms 2t). The arms 29 are connected by a cross bar 30 which serves as ejournal for the end links of the chains and as a journal for the guideor steadying discy 31.

There are two identical chains. each made up of single-plate links 32and double-plate links 33, arranged in alternation. Successive links ofcach chain are connected together h v pins 34 which are common to thetwo chains. Each pin carries betweerthe two chains a roller 35, thepreferred construe tion being shown in Fig. 5. The pins 34 areshouldered near their ends at 36 and against the shoulders 36 cap discs37 are held hy nuls 38. Certain of these cap discs are modified hyhavingl stabilizing tension members formed integrally with them, as willhe further desrribed. The links 32 and 33 arc held between discs 3T andshoulders 39. The inner races of two annular ball `hearings 40 are, hcldagainst shoulders 41 bv sleeves 42 threaded on pins 34 between shouldersil!) and 41. The outer races of the bearings lll are held in annularpockets in the opposite ends of rollers 35 by retainingr rings 43. Theseare held by cap Screws 44 or the equivalent. and are provided withgrooves which confine dust-excluding Wash ers 45 in contact with theouter cylindrical surfaces of sleeves 42. Various other conn structionsmight he used. depending in some degree on the particular type ofbearing adopted.

Each yoke 2 is adjustable toward and from the other, being held toframe. 26 by bolts 4G which pass through slots in hase plate 28. Thethrust is taken by screws 47 which serve also as means to secureaccurate adjustment. The parts are so designed that the rollerswillconforin tothe corresponding ridingr ring 15 with the discs 31 incontact with the riding ring 15. Adjustment of the carrier yokes insuresthe accurate adiustment of each chain and makesV it possihle toestablish the correct relation between the chains and the. drum, inwhich the axes lll of all une rollers are parallel to the axis oi thedrum.

The discs 31 are not designed to carry load, but merely serve asmeasuring devices, indicating when the distance from 'riding ring tocenter line of chain support 1s co1'- rect. These discs are prefera ymade of flexible material. Near the ends of the chain, radial tensionbolts 48 are used as stabilizers. These are preferably 'integral withthe caps 37 forming part of the iirst joint of the chain (counting fromthe ends). They act inltension onl the nuts bearingvagainst yoke 27 anthe bolt being free to slide downward through the yoke.

Similarly the next hinge joint is held down by sto screws 50 actingagainst the caps 37 of t at joint. The screws 50 are .locked by checknuts as shown.

Finally the middle link of the chain is stayed horizontally by bolts 51which like the bolts 48 are preferably integral with the caps 37 on thehinge pins at the ends of this link. These bolts act in tension only,their action being adjusted by means of nuts 52.

The stabilizing members 48, 50 and 51 do not prevent the rollers 35 frommoving out ward beyond their normal positions, but they are so adjustedas to resist movement inward or upward beyond the normal positions. Thusthe chain is free to assume the normal curvature under load, so that nosingle roller or pair of rollers can be overloaded. At the same time therollers are restrained against abnormal inward or upward movement suchas would tend to cause or facilitate rocking of the drum.

When the two hearingr structures are alined with reference to thc axisof the drum there is an inherent tendency to maintain alinement andequalized or substantially equal ized load on all rollers.

In Figs. 6, 7 and 8 a structure is illustrated which includes thesupporting chains, but stabilizes the chains without use of anyrestraining members acting on the chain between its end supports, suchas those used in the structure of Fivs. l to 5 inciusive.

In the structure ci tl `igs. 6 te 8 base castings 55 serve the samegeneral purptiise as the base castings 26 of Figs. 1 to 5. At each oftheir ends they are formed with. two spaced' horizontal brackets 56 andtwo alined seats 57 for thrust journals 58. Mounted on the journals 5Sare yoke structures each consisting oi' two thrust. members 59 comiectedrigidly with each other by a bar 66. Llpward or inward movements of theyoke structures are adjustably limited by stop bolts 61 which passthrough thrust members 59 and brackets 56. Downward or outward movementsof the yoke structures are cushioned by shock absorbing springs 62 whichsurround the bolts 61 and are interposed between thrust members 59 andbrackets 56.

Each yoke structure has two stop bolts 6l and two shocleabsorbingsprings 62 as is clearly indicated in Figs. 7 and 8.

As in the case of the structure of Figs. 1 to 5, the riding ring 15 ofthe grinding drum runs on a series of rollers 35 sustained by two chainsmade up of alternating singlelate links 31% and double plate-links 313.El)`he structure of the rollers and their bearilngs has been describedwith reference to igt their opposite ends beth chains are pivotallyconnected to eqn-slicing plates 63 which are jonrnalcd on the bars 66.Rollers 35 are mounted on the hinge pins connecting the chains to theplates G3 exactly as i'l lates 63 were ordinary links in the chain.

he equalizing plates 63 extend beyond the bars 6() and are rigidlyconnected together in pairs by bars 64 which are shouldered and providedwith nuts 65. On the bals 64 are mounted rollers 66 which are identicalwith rollers 35 and which are mounted on bearings identical with thoseused for rollers 35. In fact the only difference is that the bar 64(unlike the pins 34) serves as a rigid connection between the plates 62?and obviously has no hinging function.

An examination of F ig. 6 will make clear the fact that the lines ofpull of the chain on bars 62 ass below the axes of journals 58 so thattie resultant e'ect is a tendency to swin thrust members 59 downward aainst t e thrust of springs 62. Each pair o springs 62 is however ofsuilicient aggregate strength to resist this stress, plus the stressexerted directly by the loadcd drum against the rollers carried by theequalizing plates 63. The stop bolts 6() 4are so set as to prevent theupward movement of the thrust members 59 beyond normal load sup portingposition. v

The effect of this arrangement is that each pair of equalizing plates 63together with the rollers directly carried thereby and also rollers onadjacent portions of the chain, may more downward from normal positionagainst a spring bu'er in the event of excessive load. The equaliingplates are. however, positively limited in their upward movement bybolts 60 and hence cannot follow the drum upward beyond normal position.Consequently there is no tendency to cause or permit the drum to rock orpitch.

Both types ot construction have in common the idea of supporting thedrum 0n a series of chain-sustained rollers and :both embody the idea ofstabilizing the chains by restraining means which limit the upward orinward movement of the chain loop or por tions thereof. withoutrestraining out` ird movements. Since each roller is free to moveoutward if subjected to undue stress, and since the ell'ect of suchoutward movement is immediately to distribute .he excess load llt) q,1,4ve,172

among the remaining rollers the structure as a. whole nets to equalizethe load among the rollers under all conditions.

The advantage oi' the reversible drinn may be had hy the use of tworiding rings but the advantages of the self-equalizing bearin may behad, wherever a riding ring is use and we contein Alzite the use ol thisbearing in any type o mill using one or more riding rings, sindgenerally to Support any rotary iell or member whose forni is such as torender the use of a riding ring desirable.

In eert-ein of the claims we use the term inward movement" to definemotion ol? the rollers toward the axis of the drum and the termtangential movements" to define inotion of the rollers in e directionapproximately tangential to the ridingr ring. These terms are used in ageneral sense only, for lack of better terms, and are not to beinterpreted in their strict sense, for obviously the rollers do notnecessarily move in straight lines nor is their motion strictly radialor tangential. T he terms doD however, express the general directions ofthe restraining ection of the stops.

What is claimed is:--

1. The combination with :1 rotary drum of a flexible supporting membersuspended in arcuate form between points adjacent ils ends, and aplurality oi rolling anti-friction elements sustained by seid supportingmember in rolling Contact with said drum.

2. The rombinetion with e rotary drum of a llexibiesupporting membersuspended in arcuate forni between points adjacent its ends, and zrplurality of rolling anti-l"riction elements interposed in load bearingrelation between said supporting member and drum, and constructed andarranged to op crate in rolling contact with both.

3. The combination with u rotary drinn of a flexible supporting membersuspended in arcuate form between points adjacent its ends; a pluralityof rollingr antil'rietion elements sustained by seid supporting; memberin rolling;r Contact with Said drum; and stubilizing means serving toprevent seid drum from rockin.

4. The combination with :i rotary drum of a flexible supporting membersuspended in armate form between points adjarent its ends; n lurality ofrolling anti-friction ele ments interposed in load hearing relationbetween said Supporting member and drum, and constructed and urlai'igedto operate in rolling contact with both; and stabilizing means servinglo prevent said drum from rockin r.

5. Tie coinliinzition 'with a rotary meinber; of e self-equallizingrbearing therefor, COI'DpriSingr in combination u pair of snpports spacedapart; a iiexible member snspended in arcuate form between saidsupports; and e plurality oi' rollers rotatably mounted on Seid flexiblemember in load sustaining relation with said rotary member.

ii. 'l'he combination with zr rotary niember; ol n sel'iequalizingbearing structurieomprising :i pair of supports spaced apart; a. chainstructure suspended in arcuate forni between said supports und includingtwo spared parallel series of links, and n series of transverse pins,each pin servingr zit its opposite ends to hinge together adjacent linksof eneh series; and rollers rotatably mounted on said pins between saidparallel series of links in load sustaining relation with seid rotarymember.

The combination with a rotary ine1nber; of a self-eqlnilizing bearingstructure comprising e pair of supports spaced apart; a chain structuresuspended in arcuate l'orin between said supports and including twospaced parallel series of links und :i series of transverse pins. eurh.pin servire;T :it its opposite ends to hinge together adjacent links o1each series; rollers surrounding seid pins; opposed bearing racesremovably mounted in said rollers und on seid .pinne and :intl-frictionrolliruer members inter posed between said races.

8. The combinniion with :1 rotary "unn of ir supporting homing thereforcompi sing; :i Ailexilile member supported :it its ends; n

lnrality of supporting rollers mounted :it intervals on seid flexibleuwmber und in roll ing;r Contact with said drum; uml s1 :nbilixingrmeans servingy to prevent seid drum from rockin n 9. T o combinationwith :i rotary drinn, of :i supportingr bearing therefor. omprisin@r nchain supporti-d :it its ends and including e SeriesA of linlis und :iseries of hing-o pinsl connecting seid links: :1 scricsoi rollersjoui-nailed on said hinge pins` und in rolling contect with said drum;:sud stabilizing ineens serving lo provvni said drinn from rockin".

lll. 'hc rmnliiiiulion uilll :x rotar)- drum` of :i :supporting bearing;therefor, compriV :i mir of supports: a chniu suspended in e. loopbetween seid supports and including n4 series ol' links :md :l seriesnl' hingey pins xonneetingr seid links: :i series of rollers iouliuiledon seid hinge pins und in rollin;Y confort with suifl drums; stabilizingmenns carried ily said supports acting on said chain :1nd serving toprevent smid drum from roel:- inir: sind menus for adjusting saidstahiliz innr means.

ll. The rondini-Alion with a rotary drum.

of :i supporting hearing therefori comprising :i fiexible membersuf'iported ai its ends: n pluralityI ola rollers rotatably mounted nlintervals on seid lieiziblo member. :md in rollingr connu-l. with seiddrum: and n stop or stops serving: to limit the movement of one or moreof said rollers in n direction tolef.)

lio

famme ward the axis of the drum, while permitting motion in the oppositedire ztion.

l2. The combmution with a rotary drum, of a supporting bearing therefor,comprising a, chain including a series of links andA al series of hingepins connecting said iinks; a series of rollers journaled on said hingepins and in rolling Contact with said drum; and stops preventing themotion beyond their normal position of Certain of Suid hinge pinsarljnwnif the onde: of in a direction 'towmi liar-1. axis u2 "mi fla-rmwhile leaving HMH .e o :nova in lirf fing posit@ direction 13. Theoonilairifii' of a supi'im'til'wl l. oonwm lng a pair of -!o wappmyte. niY lain Structure oonnoww .1i nf: ends to s @1w ports and snspomlf-f?Mew f tim mmm @mi a plurality of follow rmutnaly woimwfl at intervals onSuid vilain structure, :nul in rollQ in@r Contact with wid drum.

14. The combination wih u. rotary drinn, of a Supporting bearingtherefor, comprising a pair of adjustable Supports, :i chain structureconnected ai, its endsy zo said snprotar; wenn pors :mei suapfrnfiadBetween ih@ Same, :L piumiiiy si iolirrs rotatably mounted atintervnfib` or und chain :fijucnra und in rolling commi, :wh said drum;and limit stops serving lo limit the movenmnt of certain of Said rollersin :who general href-tion of the axis of said flrnm withoutlimiting thismovement in iin: opposite clirevfion.

15. Tire vmnliination with n winni; drum, of n por# Uw :4am-cn :i piumawird at. in 11am in 10ll ing il merit strips ffm-tzer, @ri l Lumen-dmoveA 'i i im finis of tile mail limi! ungvnial i ,':ff mijzawm fil@middle of lin: @im wml amps permitting InovelierlL on\\zi;= 2Q' wir!Follows.

,in nmzlinamw wiwi-ooi.' 'wo inno signed our NAVI D COLE.

JULIUS G. BERGMN.-

